东亚飞蝗甲壳素提取条件的优化及衍生物壳聚糖抑菌活性研究

Experimental research of extract chitin from Meyen and analyse antibacterial of chitosan

[目的]筛选东亚飞蝗制备甲壳素的最佳条件及不同脱乙酰度和不同分子量壳聚糖的抑菌作用,并通过透射电镜(TEM)观察对壳聚糖的抑菌机制做初步探讨。[方法]改变实验条件制得含氮(N)量不同的甲壳素,通过方差分析筛选制备甲壳素的最佳条件。采用抑菌圈法,将不同脱乙酰度和不同分子量壳聚糖对5种细菌作抑菌实验,并通过透射电镜对细菌形态进行观察。[结果]壳聚糖对5种细菌都有抑菌作用,脱乙酰度在90%～95%之间,分子量在15～95 kD的壳聚糖抑菌活性较好。[结论]用东亚飞蝗制备甲壳素的最佳条件:反应温度100℃,氢氧化钠溶液的浓度8%,反应时间6 h。东亚飞蝗制备的壳聚糖有很好的抑菌作用。脱乙酰度越低的壳聚糖抑菌活性越低。当分子量大于95 kD或小于15 kD时,其抑菌活性有所降低。壳聚糖的抑菌机制是因作用于细胞壁而产生的。

[Objective] To choose the best condition of extract chitin from Meyen, and discuss antibacterial activities and mechanism of different degree of deacetylation and different molecular weight chitosan were discussed. [Methods] The various content N of chitin were obtained by change experiment condition Antibacterial experiment adopted method of antibacterial ring and bacterial shape were observed by TEM.[Results] Nine chitin containing the various N were obtained. Chitosan with molecular weight between 15-95 kD and 90%-95% deacetylation expressed high antibacterial activity. [Conclusion] The best condition of extract chitin from Meyen is as follows： NAOH consistency 8%, 100 %, 6 h, chitosan has antibacterial activities to 5 bacteria lower molecular weight and deacetylation chitosan lower antibacterial activities. Antibacterial mechanism of chitosan is deduced because of destroying cytoderm.